Hair is an appendage of the skin, consisting of keratinized epithelial cells, and is divided into long, short and fine hairs. Hair, beard, armpit hair and pubic hair are long hairs; eyebrows, eyelashes and nose hair are short hairs; and fine hair is a kind of non-pigmented, slender and very short hair, which is distributed on the face, neck, trunk and limbs. Hair is distributed on the scalp and has the role of protecting the scalp, while the color and form of hair has racial characteristics, and the texture and shape of hair plays a role in modifying the appearance. Like skin, hair is classified as dry, normal or oily depending on the amount of sebum produced and the water content of the hair. Dry hair, because of the lack of sebum, or the loss of moisture in the hair, manifests itself as dry hair, easily tangled into clumps, elasticity decreases, and a week after shampooing, the hair is still dry and loose. Neutral hair has moderate sebum secretion and hair water content, and the hair can be gently stuck up after 4-5 days of shampooing. Oily hair due to excessive sebum secretion and greasy hair, after 2 days of shampooing, the hair is oily and sticky. Healthy hair should be clean, neat, no dandruff, hair appearance black and shiny, elastic, hair stem soft and hard, moderate thickness, hair tips without split ends, hair distribution sparse and even. In order to get healthy hair, you must master the correct care method. A, shampooing and maintenance of skin, shampooing for hair care is very important, shampooing can remove scales, sebum and dust on the scalp and hair, and to the scalp to benign stimulation, similar to the role of massage, to facilitate the growth of hair. Hair should be combed before shampooing to prevent tangles and reduce hair damage. The shampoo water temperature should be 40-45 degrees. After shampooing, wrap all the hair with a large dry towel and then press gently to absorb the moisture in the hair and let it dry naturally, preferably without drying the hair with a hair dryer. After drying your hair you can use some protective water oil topically, olive oil is better. In reality, there is no certain rule on how often to shampoo your hair. Generally speaking, the shampoo cycle depends on the hair type, dry hair should be washed once a week, neutral hair twice a week, oily hair three times a week. Different seasons and occupations can be changed appropriately, winter more indoor activities, shampoo cycle extended 2-3 days, summer sweating, sebum secretion, in the field work and dust serious production environment section as appropriate to increase the number of shampoo. Second, comb your hair Combing both clean and massage the role of the scalp. Comb teeth should not be too sharp, too hard, too dense, try to use the wooden comb. Combing, first from the forehead of the hair backward comb, comb smooth, and then from the occipital hair forward comb, but also from the left to the right, and then from the right to the left combing, even force. In addition, finger comb, that is, ten fingers open, inserted into the root of the hair, with fingertips rhythmically from the forehead, temporal to the back of the occipital comb, while combing and massage, can promote scalp blood circulation, improve the nutritional supply of the hair papillae, to prevent gray hair and hair loss has a certain role. The hair should not be too long, and should be trimmed regularly. The tools for haircutting should be disinfected to prevent mutual transmission of fungus, bacteria, hepatitis virus and HIV. When there is acute or subacute inflammation on the scalp, haircutting should be suspended. Perm should not be too diligent, generally once every six months, because the cold perm essence contains thioglycolic acid, ammonia and fire alkali, which has a damaging effect on the hair, and children should not be permed. Hair dye can change the color of the hair, but hair dye contains phenylenediamine, some people can have allergic reactions after using it, so you can take a small amount of hair dye before dyeing to do patch test, to confirm that there is no allergic reaction before use. Some hair dyes contain lead salts, and long-term use can cause chronic lead poisoning in hair follicles, causing hair loss, so long-term hair dyeing is not advisable.